Extraction of Aluminum and Iron Ions from Coal Gangue by Acid Leaching and Kinetic Analyses

Minerals

Shan Feng¹  Minglei Lian¹  Zihan Zhou²  Rongli Jiang²  Deshun Kong²  Shuojiang Song² 

[1] Guizhou Provincial Key Laboratory of Coal Clean Utilization, School of Chemistry and Materials Engineering, Liupanshui Normal University, Liupanshui 553004, China;School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou 221016, China;

关键词: high iron content coal gangue;    acid leaching;    extraction of aluminum and iron ions;    acid leaching kinetic;   

DOI  :  10.3390/min12020215

来源: DOAJ

【 摘 要 】

Extracting valuable elements from coal gangue is an important method for the utilization of coal gangue. In order to obtain the suitable technological conditions and the acid leaching kinetic model of leaching aluminum and iron ions from high-iron and low-aluminum coal gangue, the effects of calcination temperature, calcination time, and acid types on the leaching results of aluminum and iron ions are studied. The results show that when the gangue is calcined at 675 °C for 1 h, then the calcined gangue powder is leached by 6 mol/L hydrochloric acid at 93 °C for 4 h, the leaching ratio of iron ions is more than 90%, and that of aluminum ions is more than 60%. Furthermore, the acid leaching kinetic equations at 30 °C, 50 °C, 70 °C, and 90 °C are studied by three kinetic models, and the apparent activation energies of the reactions are calculated by the Arrhenius formula. The results show that the leaching behavior of aluminum and iron ions conformed to the “mixing control” model equation: “(1 − x)^−1/3 − 1 + 1/3ln(1 − x) = kt + b”. The apparent activation energies of aluminum and iron ions are 55.5 kJ/mol and 55.8 kJ/mol, respectively. All these indicate that the acid leaching process is controlled by the “mixing control”.

【 授权许可】

Unknown